We experimentally demonstrate simultaneous selective detection of xylene and trichloroethylene (TCE) using multiplexed photonic crystal waveguides (PCWs) by near-infrared optical absorption spectroscopy on a chip. Based on the slow light effect of photonic crystal structure, the sensitivity of our device is enhanced to 1 ppb (v/v) for xylene and 10 ppb (v/v) for TCE in water. Multiplexing is enabled by multimode interference power splitters and Y-combiners that integrate multiple PCWs on a silicon chip in a silicon-on-insulator platform.
© 2013 Optical Society of America
Original Manuscript: July 18, 2013
Revised Manuscript: August 15, 2013
Manuscript Accepted: August 27, 2013
Published: September 20, 2013
Wei-Cheng Lai, Swapnajit Chakravarty, Yi Zou, and Ray T. Chen, "Multiplexed detection of xylene and trichloroethylene in water by photonic crystal absorption spectroscopy," Opt. Lett. 38, 3799-3802 (2013)